Let bygones be bygones

What's the meaning of the phrase 'Let bygones be bygones'? 
To 'let bygones be bygones' is to allow the unpleasant things that have happened in the past be forgotten.

Kalimat yang menyakitkan :(
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Canden, 21 April 2020 01.02 WIB

Fool's Garden - Lemon Tree

"Lemon Tree"

I'm sitting here in a boring room, it's just another rainy
Sunday afternoon. I'm wasting my time, I got nothing to do.
I'm hanging around, I'm waiting for you,
But nothing ever happens - and I wonder.

I'm driving around in my car, I'm driving too fast, I'm
Driving too far. I'd like to change my point of view.
I feel so lonely, I'm waiting for you,
But nothing ever happens - and I wonder.

I wonder how, I wonder why yesterday you told me
'Bout the blue blue sky and all that I can see is just
A yellow lemon tree. I'm turning my head up and down
I'm turning, turning, turning, turning, turning around.
And all that I can see is just another lemon tree.

Sing: dah...

I'm sitting here, I miss the power, I'd like to go out,
Taking a shower, but there's a heavy cloud inside my head.
I feel so tired, put myself into bed, where nothing ever
Happens - and I wonder.

Isolation - is not the good for me.
Isolation - I don't want to sit on a lemon tree.
I'm steppin' around in a desert of joy. Baby anyhow I'll get
Another toy and everything will happen - and you'll wonder.

I wonder how, I wonder why yesterday you told me
'Bout the blue blue sky and all that I can see is just
Another lemon tree. I'm turning my head up and down
I'm turning, turning, turning, turning, turning around
And all that I can see is just a yellow lemon tree.

And I wonder, wonder
I wonder how, I wonder why yesterday you told me
'Bout the blue blue sky and all that I can see
And all that I can see
And all that I can see is just a yellow lemon tree.